Design of a thermoelectric generator for electrical active implants

Electrically active implants for regenerative therapies (e.g. regeneration of bone tissue or deep brain stimulation for the treatment of motion disorders) are gaining on importance within an aging population. The implants must be replaced during the course of the therapy. Their performance requirements vary from a few microwatts to a few milliwatts and will keep increasing with growing functionality. In order to extend the life of electrical active implants and thus avoid the expensive and risky operations for their replacement, a considerable amount of the implant's energy requirement shall be covered by the conversion of mechanical or thermal body energy into electrical power. In this work, we present a multiphysical model of a miniaturized thermoelectric generator for electrically active implants, which uses temperature gradients in human tissue. Based on this model, we analyze the influence of the geometry and material parameters on the thermal and electrical properties and aim for an optimal transducer design. Furthermore, we use mathematical methods of model order reduction to create an accurate compact model that can be applied within a system simulation.